Less Known Solaris features: Jumpstart Enterprise Toolkit - Part 3: Files controlling the installation
I will not describe the exact process of native Jumpstart in it´s multitude of configuration files you have to modify, as the Jumpstart Enterprise Toolkit will do this job for us, but it´s important to know some of the important internals of Jumpstart. I will describe the most important files. There are varius others like
/etc/ethers or the dhcp server configuration, but as you don´t touch them manually even with the native configuration of Jumpstart i won´t describe them here.
The rules file
The first important file for the automatic installation is the
rules file. This files associates system with a installation profile. This enables you to define rules that for a certain class of machines a certain installation profile should be used, e.g. a profile for small, medium and large machines.
The first rule can be divided in it´s part like this: When the hostname of the new server is aramaki, start the script
begin on the client before starting the installation. For the installation use the profile file
webserver. After the installation execute the script
The second line is a catch-all condition. The file is used top down and the process of matching a system to a profile stops at the first match. Thus an installation for
aramaki would reach the second line. This line can be traslated like this. For any other host, use the profile
genericprofile. There is no begin or finish script.
You can´t use the the
rules file directly. The Jumpstart server provides a script to do an syntax check on te \verb=rules=. When the file is correct, the script adds it get´s renamed to
rules.ok. You don´t have to check this file manually, JET will to this job for you.
The profile file
The profile file controls what we install on the system and how we partition the disks for the installation.
You can have a multitude of profiles in your system. A profile for system with large disks, a profile for system with small disks, a profile with a selection of packages customized for a webserver, a profile customized for a developer workstation. The jumpstart framework will choose the correct one on the basis of the
The profile is capable to control almost any important parameter for the installation on the disk. You can define packages for installation or the configuration of your partitions.
The sysidcfg file
Installing the packages on the system isn´t enough to get the operating system up an running. You have to give the system a unique identity. Parameters for this identity are:
- configuration of network interfaces
- initial root password
- time zone
You can type in such information manually, but that wouldn´t be a hands-off installation. The installation process of solaris has a solution for this problem. You can set all the parameters in a file called \verb=sysidcfg=. The solaris installer will use this file to configure the system accordingly.
But: Whenever some essential information is missing, the installer will go interactive and ask for the missing information. This obviously is against our objective of an automated installation.